Any examples of a nice hand rig? Specially fingers
What you are trying to achieve cannot be nicely made in blender yet. The problem is mesh intersecting. You need to simulate mesh self-collision to get the bulging result you want. This can be done with soft-bodies but would be unusable for animating.

The best you can do is to make ton of corrective shape keys for your mesh. If you are aiming for super-real you can also add some wrinkle displacement maps and drive them with bones.